Typical plant and animal cells share a membrane, cytoplasm, nucleus, mitochondria and ribosomes. Plant cells also have a cellulose wall outside the membrane for support. Many mature plant cells have a large central vacuole containing cell sap, helping maintain internal pressure. The wall does not replace the selective membrane.
Chloroplasts carry out photosynthesis and are common in green leaf cells. Many root cells lack them but remain plant cells. Typical animal cells lack chloroplasts and cellulose walls. Photosynthetic plant cells still respire and can contain mitochondria as well as chloroplasts. Use stated structures rather than outline shape alone to classify a cell.
Example 1
A cell has a wall, a large central vacuole and chloroplasts. Which type best fits?
A photosynthetic plant cell. These structures together distinguish it from a typical animal cell.
Example 2
A root cell lacks chloroplasts. Does that make it an animal cell?
No. Many plant root cells lack chloroplasts. Other features, such as a cell wall, still support plant-cell classification.
Watch out: Plant cells respire too. Photosynthetic cells can contain both chloroplasts and mitochondria.